<template>
	<view>
        <!-- 使用自定义的搜索组件 -->
        <my-search></my-search>
        
		<view class="scroll-view-container">
		      <!-- 左侧的滚动视图区域 -->
		     <scroll-view class="left-scroll-view" scroll-y :style="{height: wh + 'px'}">
		       <block v-for="(item, i) in cateList" :key="i">
		          <view :class="['left-scroll-view-item', i === active ? 'active' : '']" @click="activeChanged(i)">{{item.cat_name}}</view>
		       </block>
		     </scroll-view>
		      <!-- 右侧的滚动视图区域 -->
		      <scroll-view class="right-scroll-view" scroll-y :style="{height: wh + 'px'}" :scroll-top="scrollTop">
		         <view class="cate-lv2" v-for="(item2, i2) in cateLevel2" :key="i2">
                     <!-- 二级分类标题 -->
		            <view class="cate-lv2-title">/ {{item2.cat_name}} /</view>
                    <!-- 当前二级分类下的三级分类列表 -->
                    <view class="cate-lv3-list">
                     <!-- 三级分类item项 -->
                       <view class="cate-lv3-item" v-for="(item3, i3) in item2.children" :key="i3" @click="gotoGoodsList(item3)">
                         <!-- 三级图片 -->
                         <image :src="item3.cat_icon"></image>
                         <!-- 三级文本 -->
                         <text>{{item3.cat_name}}</text>
                       </view>
                     </view>
		          </view>
		      </scroll-view>
		    </view>
	</view>
</template>

<script>
	export default {
		data() {
			return {
                wh: 0,
                cateList: [],
                active: 0,
                 // 二级分类列表
                cateLevel2: [],
                scrollTop: 0
			};
		},
        onLoad() {
              const sysInfo = uni.getSystemInfoSync()
                this.wh = sysInfo.windowHeight - 50
              
              this.getCateList()
            },
             methods:{
                 // 获取分类列表的数据
                 async getCateList() {
                    const { data: res } = await uni.$http.get('/api/public/v1/categories')
                    if (res.meta.status !== 200) return uni.$showMsg()
                    this.cateList = res.message
                    
                    // 为二级分类赋值
                    this.cateLevel2 = res.message[0].children
                  },
                  activeChanged(i) {
                      this.active = i
                      
                    // 为二级分类列表重新赋值
                       this.cateLevel2 = this.cateList[i].children
                       
                       this.scrollTop = this.scrollTop === 0 ? 1 : 0
                    },
                    //跳转到商品列表页面
                    gotoGoodsList(item3) {
                      uni.navigateTo({
                        url: '/subpkg/goods_list/goods_list?cid=' + item3.cat_id
                      })
                    }
             }
	}
</script>

<style lang="scss">
    .scroll-view-container {
      display: flex;
    
      .left-scroll-view {
        width: 120px;
    
        .left-scroll-view-item {
          line-height: 60px;
          background-color: #f7f7f7;
          text-align: center;
          font-size: 12px;
    
          // 激活项的样式
          &.active {
            background-color: #ffffff;
            position: relative;
    
            // 渲染激活项左侧的红色指示边线
            &::before {
              content: ' ';
              display: block;
              width: 3px;
              height: 30px;
              background-color: #c00000;
              position: absolute;
              left: 0;
              top: 50%;
              transform: translateY(-50%);
            }
          }
        }
      }
    }
    
    .cate-lv2-title {
      font-size: 12px;
      font-weight: bold;
      text-align: center;
      padding: 15px 0;
    }
    
    .cate-lv3-list {
      display: flex;
      flex-wrap: wrap;
    
      .cate-lv3-item {
        width: 33.33%;
        margin-bottom: 10px;
        display: flex;
        flex-direction: column;
        align-items: center;
    
        image {
          width: 60px;
          height: 60px;
        }
    
        text {
          font-size: 12px;
        }
      }
    }
</style>
